Hardware
326
RAID5
In RAID5, data is distributed to HDDs by striping and, at the same time, the parity (redundant
data) is distributed to the HDDs. This mode is called "striping with distributed parity".
Each of stripe x, stripe x+1, and parity (x, x+1) created from stripe x and stripe x+1 is written onto
a specific HDD. Accordingly, the total capacity assigned to the parity is just the same as the
capacity of a single HDD. If any one of the HDDs configuring a logical drive is defected, data is
still available with no problems.
RAID6
RAID 6 extends RAID 5 by adding an additional parity block (Q) created by different calculation
method such as weighting by some factor, and thus uses block-level striping with two parity
blocks distributed across all the member disks. This mode is called "striping with duplex and
distributed parity". Accordingly, the total capacity assigned to the parity is just the same as the
capacity of two HDDs. If two of the HDDs configuring a logical drive are defective, data is still
available.
HDD 1
RAID Controller
HDD 2
HDD 3
Stripe 1
Stripe 4
Stripe 2
Pality P(3,4)
Pality P(1,2)
Pality Q(3,4)
Pality P(5,6)
Pality Q(5,6)
Stripe 5
HDD 4
Pality Q(1,2)
Stripe 3
Stripe 6
Pality Q(7,8)
Stripe 7
Stripe 8
Pality P(7,8)
HDD 1
RAID Controller
HDD 2
HDD 3
Stripe 1
Stripe 4
Stripe 2
Pality(3,4)
Pality(1,2)
Stripe 3
Pality(5,6)
Stripe 5
Stripe 6
Summary of Contents for Express 5800
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Page 279: ...Hardware 279 3 BIOS Menu screen is displayed ...
Page 339: ...Hardware 339 3 BIOS will start Select Save Exit then press Enter ...
Page 444: ...444 Part Number Part number FRU File ID FRU file ID Asset Tag Asset management tag ...
Page 573: ...573 Memo ...
Page 583: ...Software 583 Memo ...
Page 690: ...Operation and Maintenance 690 Memo ...
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